Holistic evaluation of the urbane exposome on wheezing and chest infections: Outcome-wide approach

Abstract Background Noxious exposures during pregnancy are recognized risk factors for adverse respiratory outcomes in infants. However, there are few studies that consider the complex interplay of the exposome on multiple outcomes at different ages during infancy. Aim This study utilized an outcome-wide exposome approach to assess associations of pregnancy urban exposome with offspring wheezing and chest infections at 2, 6, 12, and 18 months. Methods The analysis included data from 1032 mother-child pairs from the Barcelona Life Study Cohort (BiSC) (2018-2021). In total, 44 urban exposome factors were assessed during pregnancy, including air pollution, natural space, noise, meteorology, social and lifestyle factors. Wheezing and chest infection were assessed at four time points each and analysed jointly as eight outcomes. Mixed-response sparse reduced-rank regression (msRRR) was applied while adjusting for potential confounders. Results The analysis identified 13 exposures consistently associated with wheezing and chest infection across four time points. Maternal education was the strongest protective factor, with standardized regression coefficients (β) ranging from -0.17 to -0.48 for university and -0.05 to -0.12 for secondary education (vs. primary education) (all p < 0.05). Other significant protective factors were green space size, and light-intensity exercise, with standardized regression coefficients (β) ranging from -0.48 to -0.05 (all, p < 0.05), -0.11 to -0.03 (all, p < 0.05), and -0.04 to -0.02 (all, p < 0.05), respectively. NO2 (β = 0.03 - 0.08 p < 0.05), outdoor temperature (β = 0.02 - 0.04, p < 0.05), and noise annoyance (β = 0.01 - 0.03, p < 0.05), were consistently associated with increased risk. Area-level socioeconomic status indicators showed inverse associations. Conclusions Pregnancy urban exposome may simultaneously impact multiple health parameters. Identifying key exposures may inform public health preventive strategies. Key messages • By assessing a wide range of environmental factors, the study highlights how various urban exposures during pregnancy may contribute to respiratory health risks in later life. • Identifying key exposures may inform public health preventive strategies.